with Rebecca Jordi

Category Archives: Ferns

A: You certainly can grow the native cinnamon fern, Osmunda cinnamomea, here in Northeast Florida. Cinnamon fern has a compact, horizontal rhizome which is easy to grow but prefers moist to wet soil in sun or shade. This is why you often see cinnamon fern growing in the swampy areas. It may go dormant with dry soil and be slow to establish but it is a long-lived plant. One other important note – it is seldom damaged by deer. It can grow to about 2 feet tall but will die back in the winter. It’s most distinctive feature is the bright cinnamon colored fertile fronds, produced in late spring which will die by mid-summer.

A: We have several different ferns which behave themselves to much better than Boston fern but still have similar light (shady) requirements. Here are just a few: Royal fern, Osmunda regalis, can be found growing in cold hardiness zones 3-10; shrives in rich, organic soils, can reach heights up to 6 feet but will generally die back in the winter. Good news – the deer don’t seem to like it. New growth in the spring is a pretty pale pink. Giant leather fern, Acrostichum danaeifolium, is a Florida native fern. This can grow in cold hardiness zones 8b – 12b – definitely not a northern U.S. fern. Individual fronds can grow up to 12 feet tall and the plant can spread to 5 feet wide. This fern prefers to grow in moist soil and is often found along fresh water swamps. To keep the plant looking its best in cultivated areas, consider removing old fronds and annual fertilization is not required. Maidenhair fern, Adiantum spp., is also a Florida native fern. Maidenhair fern has delicate fronds and is fund more often in Central and Southern Florida in cold hardiness zoned 9-11 but could be planted along the eastern coastline. This fern might be a good choice for smaller landscape areas as it grows 3 feet tall and 3 feet wide. The southern maidenhair and brittle maidenhair grow best in alkaline soils while others grow best in acid soils. With so many of our along the coast having high soil pH readings, this is a good plant to consider for shady sites. It will cascade over the side of a container in a shady garden spot. Some of the available species include: Adiantum capillusveneris, southern maidenhair, 1.5 feet tall; A. hispidulum, rosy maidenhair, one-foot-tall, young fronds rosy brown; A. pedatum, western maidenhair, 1 to 2.5 feet tall, most popular one grown; and A. peruvianum, silver dollar maidenhair, 1.5 feet or more tall, leaf segments quite large, up to 2 inches wide. Then consider other common ferns such as holly fern, autumn fern, and staghorn fern.

A: Thank you so much for sending me a photo, which helped me narrow the field. I believe your palm is actually an Australian fern tree, Sphaeropteris cooperi. It was introduced to the United States from Australia. The Australian tree fern is a tropical, single-trunked, giant fern. It has long, bi-pinnately compound, lacy leaves with a fine texture. The 1 to 1.5 foot long leaves form a handsome canopy and impart a tropical effect. The fern produces one trunk with a woolly appearance, and the trunk may grow to a diameter of 1 foot. This plant reproduces by spores found on the undersides of mature leaves – typical of many ferns. These spores cause problems for Hawaii’s native flora as it reproduces quickly and overtakes the native plants. The fern tree, also called Coopers Cyathea, is considered invasive in Hawaii. It grows in cold hardiness zones 10a – 11, which is South Florida for us. This means the tree fern really should be located in a patio or screened area here in Northeast Florida. Consider keeping it protected if we get temperatures below freezing. It grows at a slow rate and reaches heights upward to 18 feet with a potential 15 foot spread. Australian fern tree prefers shady sites and will show browning on the fronds if it receives direct sunlight, especially intense afternoon sun. It prefers sandy, moist, well-drained soils. This plant is not salt tolerant, therefore it should not be planted along the coastline. For more complete information please look over the University of Florida publication: http://edis.ifas.ufl.edu/fp557

A: I am so glad you brought in a photo of the fern as this made it very easy for me to identify the fern as Resurrection fern, Pleopeltis polypodioides. This plant is native to Florida and found in moist areas and sometimes on the trunks of trees. Resurrection fern is classified as an epiphyte, similar to Spanish moss and “air” plants. It uses the trunk of the tree as a place of attachment but does not derive any of its nutrients from the tree but instead takes moisture and nutrients from the outer surface of the bark. Because it does not form true roots it must live in areas where the air is continually moist. The name resurrection comes from the plant appearing to be dead and dried up but once the rains come and moisture returns the plant suddenly comes back to life. Resurrection fern is not a parasite and it will not kill the tree. Having Resurrection fern on the trunk of the tree does not indicate the tree is dying or in decline. However, it does indicate the area is moist and conditions are perfect for the fern to thrive.